1. Field of the Invention
The present invention relates to an image transmission technology.
2. Description of the Related Art
Information on a product or the like is encoded and printed on paper, as typified by a barcode and the like. The information printed on paper is acquired by reading it by a reader, and used to product management and the like.
Not only information on a product but also information such as an image is encoded and printed on paper. An image input/output apparatus scans paper bearing the encoded image to decode the encoded image and restore the original data. The user can obtain a printed material by printing the restored original data.
There has been proposed a technique of printing encoded data on paper and restoring it by a multi-functional peripheral. For example, according to a technique disclosed in Japanese Patent Laid-Open No. 2001-344588 (U.S. Pat. No. 6,634,559), an original file is encoded and printed on paper together with its thumbnail. The original file can be printed by scanning the paper by a copying machine.
When scanning and transmitting a document image, the resolution of the scanned document image needs to be converted in accordance with a transmission resolution designated by the user or a resolution that may be processed by a destination device (e.g., FAX). In this case, if an encoded image prepared by encoding information exists in a document image, the resolution of the encoded image is also converted together with the document image, and information of the encoded image may be lost. Such an encoded image cannot be decoded at the destination of the document image.
If the resolution of an image containing an encoded image is converted, no encoded image can be decoded at the destination.